Don't quote me on this because I don't know if it is a true statement but,I "believe" that if you scale the pelivs (mainbone) rather than the root_transfer, it scales the complete model including hit boxes, but is only true dependent on how the hit boxes were compiled into the model at compile time. Most of the time when I compile a model for SFM, I remove all hitbox and joint/bone constraint references from the qc. They aren't required at the present time in SFM (so none of my models would be usable in a normal game.) If SFM get to the point of including physics, well then I'll have to reconsider these elements.